This part is a kind of semiconductor called HD-081-A.

Function of this product has 10/100BASET-T TRANSFORMER.

Manufacturers : Taimag

Image and pinout :

Some of the text within the PDF file :

NO: RD-SD-HD-081-A DATE: 2014/04/09 T(REV:A6) 10/100BASET-T TRANSFORMER MODEL NO.: HD-081-A FEATURE: RoHS Compliant RoHS peak solder rating 260℃/ 3~5 Sec Do not use material and use that the prohibition that SS-00259 stipulates Designed to meet IR requirement Operating temp.：0℃ ~ +80℃ Specifications @ 25℃ OCL : 350 uH Min @100kHz ,100mv / 8mA DCR: 1.5 Ω Max. LL: 0.5uH Max. Cw/w:30 pF Max. MSL=2 Part Number HD-081-A Turns Ratio （±3%） Insertion Loss （dB MAX） 1 - 100MHz -1.0 Cross Talk （dB MIN） 1-100 MHz -35 1-40 -16 Return Loss (dB MIN) 40-80 80-100MHz -16~-10 -10~-8 Common Mode Rejection （dB MIN .） 1-30 30-50 50-100 MHz -35 -33 -30 HIPOT（VAC） 1CT:1CT 1500 SCHEMATICS: DIMENSION: mm TOLERANCE: ±0.25 Packing： NO: RD-SD-HD-081-A DATE: 2014/04/09 T(REV:A [ ... ]

HD-081-A PDF Datasheet Download